Determination of Se, As, Cu, Pb, Cd, Zn and Mn by anodic and cathodic stripping voltammetry in marine environmental matrices in the presence of reciprocal interference. Proposal of a new analytical procedure

Arsenic(III), selenium(IV), copper(TI), lead(II), cadmium(II), zinc(II) and manganese(II) have been determined in environmental matrices by differenti al pulse cathodic (DPCSV) and anodic (DPASV) stripping voltammetry. The vol tammetric measurements were carried out using a conventional three-electrod e cell and the ammonia-ammonium chloride buffer (pH 9.4) as the supporting electrolyte. The analytical procedure was verified by the analysis of the s tandard reference materials: Sea Water BCR-CRM 403; Lagarosiphon Major BCR- CRM 060; and Cod Muscle BCR-CRM 422. The precision, expressed as relative s tandard deviation, and the accuracy, expressed as relative error, were, in all cases, lower than 5%; the detection limits, for each element in the exp erimental conditions employed, was approximately 10(-9) M. The standard add ition technique significantly improved the resolution of the voltammetric m ethod, even in the case of very high metal concentration ratios. (C) 2000 E lsevier Science B.V. All rights reserved.